Lubricant for split dies



- especially adapted for split or open dies.

' characteristic of these necks are not filled out the wire.

mor positively in nail in cut-oil? machines for spring wire,

' get a well-filled Patented Nov. 9, 1943 UNITED STATES PATENT OFFICE Samuel Epstein, Bethlehem,

Lebanon, Pa., assignors Oompany,acorporat Thi invention relates generally to the manufacture of wire, rod, nails, carriage bolts, screws and the like, and more particularly to lubricants, forming such articles in Standard carriage bolts have roundunslotted heads and square necks, although special typ s are also made with bevel, countersunk or askew heads or ribbed necks. Theenlarged necksare erly to obtain sharp, unroundededges.

bolts, yet with ordinary die lubricants it is diflicult to fill them out propand John R. Kreiser, to Bethlehem Steel ion of Pennsylvania No Drawing. Application September 16, 1941,

, Serial No. 411,010

6 Claims. (01. 252-22 1 coating isgenerally .used for this type of work, particularly for nail wire, the sul or rust coating being applied by holding the rod in a fine water spray. afterv washing'and before liming the rod.

The heavier suldecreases the slipping but it also increases the die wear. Furthermore, it is dim- "cult to obtain a uniform coating of sul as this The split or open dieused in cold-heading carriage bolts and the like is made in two pieces, so that the die opening may breathe or give slightly to prevent sticking of th'e-work-piece, Befor entering the die the wire is cleaned, coated with lime, and covered with a suitable lubricant to protect the wire and die surfaces.

For a long time it has been known that dropping a bit of oil on the wire as it went into the heading die would cause rounded instead of sharply filled out edges on the necks of carriage bolts. That is why oil cannot be used as an additional lubricant on such work. The rounding of the edges isgenerally attributed to oil being trapped and forming pockets in the die crevices. However, even very minute amounts of oil produce neck is obtained with a less slippery coating on A less slippery-coating not only gives better filled out necks, but also'better filled out and rounded heads. This'is especially important for wood screws. It also gives a wire which is held making machines, so that nail is cut by the dies with -Such wire also works better due to less slippage in the guide rolls, so that moreeven lengths are obtained and more uniform springs.

Various recourses have hitherto been tried to out neck, Thus bright drawn wire, with no coating at all has been used. This gives a well-filled out neck but leaves the heading operation without lubrication and does not protect the wire from rusting; A heavier sul a more evenly pointed less whiskering.

.the same coil. Thinner 10' may vary considerably from coil to coil and within lime may avoid undue clogging in the dies {and give a better filled out neck; also because less lubricant is taken up by thinly limed rod the coating may be less slippery. An additional pass through the drawing die also 1 makes for -'a thinner and'less slippery coating.

This is,'of course, expensive.

One, object of our invention, therefore, .is to provide an improved lubricant for split die work. Another object is to give better filled out necks to carriage bolts and the like. 1

A further object is to produce more fully rounded heads on .wood-screws andthe like.

Still a further object is a lubricant which result in better and more uniformly pointed nails, and in less slippage in the guide rolls of spring wire cut-ofl machines.

Other objects, purposes and advantages of this invention will more clearly appearin the following pages of the specification and in the appended claims, and we now set forth in detail the particulars of our invention.

We have found by experiment that adding an ingredient to the die lubricant which makes for less---. slipperiness, calcium resinate for instance, definitely gives the most uniform and dependable results with split dies.

The addition of about 8 per cent of calcium resinate :by weight will improve any lubricant ordinarily used with split dies, but we have found the following mixture, in approximate parts by weight, to be quite thebest for the purpose:

. All the components in this lubricant are dry and water repellent, with sufficiently high melting points not to cause smearing or caking in the dies, and all except calcium resinate have high lubricating values. Even calcium resinate, although not a particularly good lubricant, is a soft material, and has no abrasive effect such as lime, for example, sometimes has. The calcium resinate makes for a drier and less slippery wire which aids materially in filling out the neck.

The substance of lowest melting point herein, the synthetic wax "Acrawax C (cetyl acetamide, melting point, 275 F.) helps to spread the lubricant over the limed wire. Natural waxes or wax-like substances of approaching melting points, such as ozokerite or montan or carnauba wax, or blends thereof, may be substituted in equal proportions for this ingredient. Hexachlorbenzene, melting point, 440 F., has good lubricating properties and is water repellent. The graphite also lubricates, gives a distinctive pleasing sheen, and aids in maintaining a stable lustrous coating in shipment and storage.

If the darker color due to the graphite is not desired, the finished bolts may be tumbled and blued or otherwise conventionally processed to remove or change the color, or the following white lubricating mixture may be used, in parts by weight Hydrated lime l8 #1 Penola V. D. grease Calcium resinate 2 The above-mentioned #1 Penola V. D. grease is an ordinary lime-base grease such as is used 'in drawing wire, and other greases of this type such substitutions, modifications or equivalents .wire springs, bolts,

thereof as are within the scope of the invention and claims.

Having thus described our invention, what we claim as new and useful and desire to secure by Letters Patent is:

1. A lubricant for use in the manufacture of wire springs, nails, bolts, screws and the like comprising, in approximate parts by weight, 2 to 3 calcium resinate, 2 to 4 wax of melting point approximately 275 F., 10 to 12 hexachlorbenzene, and 5 to 6 graphite.

2. A lubricant for use in the manufacture of wire springs, bolts, screws and the like comprising, in approximate parts by weight, .2 to 3 calcium resinate, 2 to 4 montan wax, 10 to 12 hexachlorbenzene, and 5 to 6 graphite.

.3. A lubricant for use in the manufacture of screws and the like comprising, in approximate parts by weight, 2 to 3 calcium resinate, 2 to 4 carnauba wax, 10 to 12 hexachlorbenzene, and 5 to 6 graphite.

4. A lubricant for use in the manufacture of wire springs, bolts, screws and the like comprising, in approximate parts by weight, 2 to 3 calcium resinate, 2 to 4 cetyl acetamide, 10 to 12 hexachlorbenzene, and 5 to 6 graphite.

5. A lubricant for split dies comprising, by

weight, approximately 2 parts calcium resinate,

4 parts cetyl acetamide, 10 parts'hexachlorbem,

zene, and 5 parts graphite.

6. A lubricant for use in the manufacture of wire springs, nails, bolts, screws and the like comprising a mixture of calcium resinate, hexachlorbenzene, wax having a melting point approaching 275 F. and graphite.

SAMUEL EPSTEIN. JOHN R. ER. 

